If you sing the chant too slowly, you lose the sense of the chant, you lose the meaning because the chant, the text, becomes less and less understandable. Yes, you have to understand what the text is saying. You don’t have to be a Latin scholar to know that (though that helps a lot). People in the pews have books they can follow, that is true. But singing the chant too slowly risks breaking the integrity of the text’s meaning. Try listening to an audio book at a really slow rate of reading. As you turn the pace down, it eventually becomes incomprehensible.
If you sing chant too quickly, you tend to retain the meaning of the text, but you put its sacral character at risk. The texts are sacred. They deserve respect and time. They must not be rushed. They must be savored. Chant that is rushed has a nervous, jittery quality to it. It lacks the essential quality: it isn’t prayerful. The pace of a Mass must not be lugubrious. Every Mass and every element of Mass must retain a sense of progress, of moving forward towards a goal. When you tear through a chant, you might be making progress, but you lose the essential sacral sense. Every word of the chants are the voice of the Church singing with Christ’s own voice. Christ is the true Actor during Mass. He borrows us, the baptized, and uses our gestures and song.
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